Field of the Invention
The present invention relates to a canned motor pump for a vehicle in which a can structure is interposed between a rotor and a stator.
Description of the Related Art
Most modern day vehicles are provided with a water pump which circulates cooling water and an oil pump which circulates oil. In particular, water pumps, by way of example, the water pump can be divided into engine powered water pumps which operate by receiving power from an engine through a belt connected to an engine rotary shaft and electric water pumps which operate on electricity from a battery. Since the electric water pumps do not require power from the engine, they improve fuel efficiency and the ability to precisely control the temperature of cooling water.
In addition, when a vehicle such as an electric vehicle or a hybrid vehicle which uses a drive motor as a power source is running using purely the power of a motor, the use of an electric motor for the water pump is necessary since the drive motor sometimes turned off during operation.
The structure of a typical canned motor pump is configured such that a can structure is interposed between a rotor and a stator, a hydro unit extends toward the rotor so that the rotor is submerged into water. Here, the can serves as a compartment that separates the rotor from the stator, and is separately fabricated by injection molding.
However, when the can motors are made in the above manner, because the can is made separately and then is inserted into the state core, an assembly gap is created which increases an air gap therebetween. The presence of such an air gap causes vibrations and noise, which are problematic (i.e., vibrations can cause parts to come loose and such noise is not desirable to consumers).
The foregoing is intended merely to aid in the understanding of the background of the present invention, and is not intended to mean that the present invention falls within the purview of the related art that is already known to those skilled in the art.